Multiple hydraulic drive



Nov. 10, 1931. JJP. FERRIS 3 iwL'rIPLE mnmumc- DRIVE Filed Feb. 29-.1928 3 Sheets-Sheet 1 9 R. L/bHNEFEHZS...

ATTORNEX;

Nov. 10, 1931. v J. P. FERRIS ,8 MULTIPLE mR uLId DRIVE Filed-Feb. 29..1928 3 Sheets-Sheet 2 INVENTOR. LZb HNEEEHJS A TTORNE Y.

40 Another object is the provision of improved Patented Novt 10, 1931JOHN P. FEBBIS, F MILWAUKEE, WISCONSIN,

Assrenoa r0 THE OILGEAR COMPANY,

OF MILWAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN murmur: mmnuc DRIVEApplication filed February 29, 1928. Serial No. 257,935.

, This invention relates to multlple hydraulic drive systems foreffecting the simultaneous operation of a plurality of independentelements at accurately controlledspeeds.

For purposes of explanation the invention will be described as embodiedin a special type of crank shaft lath, wherein it is utilized as a anaccurate feed mechanism for a plurality of independent tools, althoughit is capable of application to other types of machine tools and toother widely varying, arts, such for instances asa multiple pumpingsystem for oil wells. 3

One object of the present invention is the provision of a hydraulicsystem through which a pluralityof independent elements may besimultaneously driven at accurately regulated rates from a single powersource. Another object is the provision in a mule 2 'tiple drive system.of the character mentioned of means for effecting an accurate control ofthe rate and extent of movement of the several driven elements.

Another object is the provision in'a multiple drive system of thecharacter mentioned of means for compensating for leakage losses tothereby maintain proper phaserelation between the several driving means.A'notherdabject is the provision in a mul tiple drive system of thecharacter mentioned' of means for temporarily concentrating theentire'force of the power source upon any of the several-driving means;t

Another object is the provision in a-multinle drive system of thecharacter mentioned of means for maintaining a different phase relationbetween the several driving means so that one "or more may complete thework-1 ing stroke ahead of others.

flexible connections for transmitting driving liquid to each hydraulicdriving means. Other objects and advantages will appear fromthe-following description of an' illustrative embodiment of the presentinvention.

In the drawing's': I Figure 1 is a fragmentary plan view of crank shaftlathe equipped with a multiple hydraulicfeed system embodying thepresent 5 invention.

(Fig.2); bya gear 16. and at the other end by "axes of the two pins 14and 17 of each frame Fig. 2 is a transverse section taken substan:tially along the line 2-2 of Figure 1.

' Figs. 3 and 4 are longitudinal sectional views of two flexiblyconnected fluid conducting links, which together form a flexibleconnection for conveying driving liquid to and from each feed cylinder.These sections are taken substantially along the lines 3-3 and 4- 4,respectively, of Figure 2.

Fig. 5 is a diagrammatic view of the hydraulic system. 7

The lathe shown in Figures 1 and 2 is designed to finish in oneoperation the cheeks a of the several'cranks b of a crank shaft 0 andalso theseveral crank pins thereof. The crank shaft is shown mounted atone end upon a (lead center 10 and at the other end in a rotary chuck 11of a well-known type driven clockwise (Fig. 2) by an appropriate gear12. The crank shaft is thus rotated about its true axis causing theseveral pins ll thereof to follow circular orbital paths concentric withthe axis. A plurality of tool supporting frames 13 are mounted totranslate within circular orbital paths coextensive with the paths ofthe several crank pins (1, respectively, and in phase therewith. In thisinstance each "frame is supported at one end upon an ec centric pin 14on a shaft'15, driven clockwise an eccentric pin-17, on a shaft 18driven in' the same direction by a gear 19. The three gears 12, 16 and19 are driven at the same rate through a gear 20 meshing therewith. The1 are oifset equal distances and in the same direction from the axes oftheir respective shafts 15 and18, the extent and direction of oilset ineach instance being equal to the ex- I tent and direction of oflfset ofthe corresponding pin (1 of the crank shaft 0, so that each frame movesparallel to itself and in the same phase as the corresponding crankpind.

, Each frame carries atool feeding cylinder 21. 22, 23, or 24 whichmov'es'in unison therewith and encloses a piston 25, 26, 27, or 28closely.v fitted for lengthwise reciprocation therein. Each frame isalso transversely bored to'receive and guide arod 29, 30, 31 or 32connected with the associated piston and carryingalathe tool 33, 34, 35,or 36, adapted to operate upon one of the several pairs of cheeks a andcrank pins (1. Each tool is given two distinct motions :-(1) a circulartrans- 5 latory motion, imparted from the translatory motion of itssupporting frame, by which it is caused to follow a crank pin (1 in itscircular travel about the axis of the crank shaft, and (2) a rectilinearmotiqn toward and from the axis of the crank pinimparted by the movementof its associated piston lengthwise of the cylinders 21, 22, 23 or 24. IThe several pistons 25, 26, 27 and 28 are actuated and controlled by amultiple hydraulic drive system such as will now be described. In thissystem (shown diagrammatically in Figure 5) the rear ends of the severalfeed cylinders 21, 22, 23, and 24 are hydraulically connected to theforward ends of several impeller cylinders 37, 38, 39 and 40,respectively, through appropriate leads 41, to be hereinafter described;and the forward ends of the several feed cylinders are hydraulicallyconnected to the rear ends of the several impeller cylinders,respectively, through similar leads 42. The several impeller cylinderscontain coacting pistons 43, 44, 45nd 46, respectively, which aresimultaneously driven by anappropriate crosshead 47 to which they arerigidly connected through appropriate rods 48. The arrangement is suchthat during each advance stroke of the cross head 47 each of the severalpistons 43, 44, 45, and 46 will advance and force liquid at adefiniterate through the leads 41 into the several feed cylinders tothereby advance each of the several pistons 25, 26, 27, and 28 at adefinite rate, the liquid discharged from the forward end of'each feedcylinder returning to the rear endof each impeller cylinder through therespective leads 42;, and upon each return stroke of the crossheadtheseveral pistons 25, 26, 27 and 28 are retracted by liquid deliveredthrough the re- 45 spectiveleads 42 from the rear ends of the "impellercylinders. The several tools 33, 34.

35 and 36 are thus individually fed at definite I through a link 75 withan arm 76 projecting from the lever 51, so that the lever is caused t estoward and from the respective crank pmsd in accordance with thedirection and rate of movement of the cross-head 47.

The cross-heads 47 is hydraulicallyt driven' in both directions and atcontrolled speedsby liquid supplied from a reversible flow, variabledisplacement pump 49 of a well known type. The pump shown is fullydescribed in my copending application Serial No. 199,925, filed June 20,1927, and it will sufiice here to state that it is driven atconstantspeed from an appropriate source through a shaft 50, thedirection and rate of liquid dischar ed thereby beingcontrolled byalever 51. ith the control lever 51in the intermediate position shownpump dischar zero; When shifted toward the right hquid I 05 isdischarged through outlet 52 at a ratedependent upon the extent ofmovement of the ever, an liquid returns to the pump through outlet 53;and when the lever is shifted toward the left liquidis dischargedthrough outlet 53 at a rate dependent upon the extent of movement of thelever, and liquid then returns to the pump through outlet 52. In allpositions of the control lever the by cause the cross-head 47 to executea prede- To this end the termined operating cycle. pump control lever 51is placed under the control of an appropriate cam, mounted for movementwith the cross-head. Cam shown includes a plate 61 fixed to thecross-head and having an upstanding portion '62 of irregular form shapedto provide a straight edge 63, and a broken inclined edge .64,interrupted b a short straight portion 65. A cam bloc 66, adjustablyfixed to the plate 61 and spaced from the upstanding portion 62."

In this instance the two main ciris also of irregular form. One sidethereof i is shaped to match the portion 62 and the 7 other side isshaped to provide three straight gortions 67, 68 and 69 disposed atdifferent istanees from the longitudinal center of the block. A pin 70,carried by one. arm of a bell-crank 71, is arran ed to 'coact with thefaces 63, 64 and 65 o the'portion 62 and the faces 67, 68,'and 69 of theblock to determine the position dfthe bell-crank during movement of thecross-head. The bell-crank is fulcrumed, as at 72, upon an appropriatefixed bracket 73, and is yieldably urged to swing clockwise by theaction of a spring 74. The other end of the bell-crank is connected to gupon its fulcrum 77 in accordance with the action of the bell-crank.

With the parts in the position shown the pin 7 0 is held by the spring 74-in intermediate neutral position against the inclined por-" tion 64 ofportion 62, so that the lever" 51 is also in neutral position, there isnoflop in leads 57 and 58 and the crm-headiiflis at rest. To start. thefeed motion thejjl'ever 51 1S manually swung toward the right to therebyshift the bell-crank and pin 70 toward the left and cause the pump todeliver liquid at a high rate through-the lead 57 to the rear.

end of the motor cylinder 59, to thereby advance the piston 60and-.cross-head 47. The hand lever 51 is'then released and the pin 7 0'tool. For this purpose a pair of independent- 1,ss1,2ss' I 3 first ridesupon theiface 67 of the advancin an appropriate manner to the frame ofthe ing cam block 66 to thereby maintain the admachine, the leads beingcompleted by pairs Vance of the cross-head at a relatively rapid offlexibly connected .fluid conducting links rate. This advance continuesuntil the pin 85 and 86 through which the several passages 70 leaves theface 67 and swings toward the 41 and 42 communicate respectively withright into contact with face 68, thereby the opposite ends of theseveral moving feed swinging the lever 51 apredetermined discylinders21, 22', 23 and '24. ta-nce toward neutral position and causing a Twolinks of a coacting pair are shown reduction in pump displacement. Thecrossin section in Figures 3 and 4. Each link conhead then continues toadvance at a,slower tains two longitudinal passages 87 and 88 75 rateuntil the pin 70 leaves face 68 and'makes or .87 and 88.- A pintle 89fixed in and cont-act with face 69 to effect a similar adprojectinglaterally from one end of link 85 justment of lever 51 and a furtherreduction is closely fitted to rotate within the adjacent in pumpdisplacement. The cross-head then end of link 86 and provides a swivelconneccontinues to advance at a ill Slow r ra e tion therebetween;Pintle 89 is removably so until the pin 70 leaves face 69 and swingsretained in'link 86 by appropriate means such intocontact with 'face 63of portion 62. as a screw 90 and washer 91. The other end This actioncauses the lever 51 to swing of link 85 is mounted to swing upon asimithrough neutral position into an extreme polar pintle 92 fixed inand projecting from a sition, toward the left, so as to reverse thebracket 93 projecting from the rail 84. Pintle e5 pump and cause thesame to deliver liquid at 92 is provided with two longitudinal pasa highrate through lead 58' into the forward sages 94 and 95 which communicatethrough end of the motor cylinder 59, whereupon the ports 96 and 97 andpipes 41 and42" with cross-head begins areturn movement at relthetransverse passages in the rail 84, and

a ively high Speed. This movem t nwhich also communicate through ports98 90 tinues until the rate is reduced by the action nd 99 with thepassages 87 and 88 in the of inclined face 64 upon the pin 70. The link85. Similarly passages 87 and 88 in straight portion permits thecross-head to link communicate respectively with pastravel for a shortdistance at low speed after sages 87 and 88 in link 86 through longi- 30which the pin 7 0 is ultimately returned to the t dinal passages =2 00and 101 in the pintle 89.

original neutral posit-ion by the continued A thi d' i fl 102 fi d i thd f li k 86 action of c 64 and e cross-head g i is closely fitted forrotation within the end j comes to rest. As hereinabove pointed out hd103 of on of the feed cylinders. A the variable speed advance andreturn movel ngitudinal passage 104-in pintle 102'con- 35 ments of thecross-head are transmitted to nects passage 87' i li k 86 with a. a agon the several pistons 25, 26, 7, and 28 ro g 105 leading to the rearend of the feed cylinthe several lmpeller cylinders 87, 38, 39 and d anda longitudinal passage 106 connects 40 to efiect the'advance and returnof the passage 88 ith a i 107 l di t the several tools toward and fromtheir respecf d d f th f d li d Th b tiW fi l P I draulic leads for bothends of each feed cylin-. 105

Provision s also made for individually d are th id d by a in l pair of.illmltlng the extent of advance a return f links-connectedin such manneras to permit ea h pls on 2 2 27 nd 28 t0 the e y PI free movement of thecylinder with its supgvide an extremely accurate control for each ortingframe13. i

Each lead 41 and 42 is connected with a 1y ad ustable hmitmg stops areprovlded fo high pressure relief valve 108 of awell known each tool.Inthe form shown these stops comty e, I this in tance each of theseveral prise a pair of set-screws 78 and 79 mounte relief valves ismounted upon the rail 84 in in suitable lugs 80 and 81 projecting fromcommunication with one of the passages 41' .50 h t l carrying frame 13-Eaeh pair of or 42 in the rail, the liquid passing each valve. 1

screws coacts with an intermediate stop 82 being permitted to escapethrough a pipe 109 projecting-from h of h r dS 29,3 31 into alongitudinalpassage 110 in the rail. and.32 through a slot 83 in eachframe-.' The ,Passage 110 communicates through an approengagementof stop82 against, screw 78 limits priate lead 111 and connection 55 with the55 the advance of the associated tool and the liquid reservoir in thebase of the pump. A 1 engagement of stop 82 with screw 79 limits secondlongitudinal passage 112 in the rail is p the ret rn St k of themaintained flooded with liquid under low In the machine shown each ofthe several pressure supplied from the pump through ihydraulic leads 41and 42, indicated diagramthe connection 54 and lead 113. A checkvalvemati'cally in Figure 5, consists in part of sepa- 114 between thepassage 112 and-each ofthe rate pipe connections through which theopseveral passages 41' and 42' pe'rmitsthe ad positeends of the fixedimpeller cylinders mission of liquid; thereto from passage 112 37 38,39, and 40 communicate respectively whenever the pressure in any of theseveral with separate passages'41' and 42 leading main leads'41, and 42falls below that in the n transversely througha fixed rail 84 attachedpassage 112. These leads are thus always 133:-

maintained flooded with liquid under pressure. A third longitudinalpassage 115 in the rail is permanently connected through a lead 116 withthe power lead 57 leading to the rear end of the motor cylinder 59. Acheck valve 117 between the passage 115 and each of the passages 41permits liquid to escape from any of the leads 41 wheneverthe pressuretherein exceeds the pressure in the passage 115.

The stroke of the cross-head 47 is such that it continues to advance fora brief time interval after all of the tool feeding pistons 25, 26,27and 28 have been arrested by the engagement of their respective stops 82against the coacting screws 78, and such that it continues its returnmovement for a brief time interval after all of the feed pistons havebeen arrested by the engagement of their respective stops 82 against thecoacting screws 79.

During the continued advance of the sev-' eral impeller pistons 43, 44,45 and 46, after the advance of the corresponding feed pistons has beenarrested, the excess liquid in the several leads 41 escapes through thecorresponding high pressure relief valves 108. and liquid under lowpressure is admitted to the several leads 42 through the correspond ingcheck valves 114 to thereby maintain these leads and therear ends of theimpeller cylinders 37, 38, 39 and 40 flooded. The several ,feed pistonsare thus in readiness to start simultaneously on a return movementimmediately upon the reversal of movement of the cross-head. In asimilar manner excess liquid is permitted to escape from the severalleads 42 through their respective high pressure relief valves 108, andliquid is 'admitted to the several leads 41 through their respectivecheck valves 114 to keep the same flooded, during the continued returnmovement of the several impeller pistons after the return movement ofthe several feed pistons has been arrested by the stop screws 79; andthe several feed pistons are thus in readiness to advance simultaneouslyimmediately upon the next advance of the cross-head. A hydrauliccompensating system is thus provided with functions to maintainadefinite operating phase relation between the several feed pistons inspite of any leakage lossesin the system.

It will be noted that during both the advance and return strokes of theimpeller and feed pistons the several cylinders of each group receivetheir supply of liquid primarily from the discharge of liquid from theseveral cylinders of the other group. To

make the rate of discharge from each cylinder of one group exactly equalto the intake demand required by a connected cylinder of the other groupis a practical impossibility due to unavoidable leakage and mechanicalinaccuracies. This leads to serious difiiculties. For instance, ifduring the return stroke of piston 25 the rate of discharge from therear end of cylinder 21 be only slightly greater than the rate of suppldemanded by the cylinder 37, an excessive ack pressureis set up in thelead 41 causing the piston 25 to stioned that during the advance strokethe 0 rate of discharge fromthe forward end of each feed cylinder isslightly less than the supply demand of the rear end of the associatedimpeller cylinder, liquid being admitted to each of the leads 42throughthe check valves 114 tomake up for this deficiency and therebykeep the impeller cylinders full. During this advance the several checkvalves T17, hereinabove mentioned, are kept closed by the pressure inpassage 115 transmitted from the working pressure in the lead 57 bywhich the piston 60 is advanced. With the cylinders and rods thusproportioned the rate of discharge from the rear end of each feedcylinder, during, the return stroke, is slightly as i in excess of thesupply demand of the forward end of the associated impeller cylin-- der.During the return stroke however the pressure in the lead 57 is ofcourse reduced,

since this leadis then only carrying the dis- 10o charge from cylinder59, and. the several check valves 117 function to permitthe escape ofexcess liquid from the several leads 41 and thus prevent the building upof excessive pressures therein. The check valves 117 tolo:

gether with check valves 114 thus effectively compensate forinequalities between rates of discharge and supply demands of theconnected cylinders.

vA brief description of the operation of the 1 machine will now begiven. Let it be assumed that the crank shaft 0 has been applied, asindicated, and that the three gears 12, 16, and 19, are rotatingclockwise (Fig. 2) under the action of the driving gear 20, so that the'11:

crank shaft is rotating clockwise, the several crank pins (1 arefollowing a circular path, and the several tool carrying frames 13'aretranslating with a circular motion similar to and in exact phase withthe'respective crank pins. Let it also be assumed that the severalfeeding pistons 25, 26, 27, and 28 are retracted so that the severaltools 33, 34, 35 and 36 'are withdrawn from the work, and

that the cross-head 1,47, block 66, pin 70,

and controllever 51 are in the respective positions indicated in Figure5. To start an operating cycle the operator shifts the hand lever "51into right extreme position, whereupon the pump delivers liquid'at ahigh rate o by cylinder 37, an excessive back 75 through the lead 57 andthe cross-head 47 and" impelling pistons 43, 44, 45 and 46 advancerapidl The operator then releases the lever 51 an permits the in 70 toride upon the face 67 of the cam lock and the rapid ad vance continues.During this advance the several feed pistons 25, 26, 27 and 28 areadvanced at a corres onding rate causing the several tools to a yancetoward the work.

Just before the tools are actually engaged between the several airs ofcheeks a on the crank shaft the pin 0 leaves face 67 and contacts withface 68 of the cam block to thereby reduce the rate of advance of thecross-head 47 in the manner hereinabove described, whereupon the rate ofadvance of the several tools is correspondingly reduced to a I rateappropriate for a light cutting feed.

This rate of advance continuesuntil just prior to actual engagement ofthe cutters with the several crank pins, at which time the pin leavesthe face 68 and contacts with face 69 to thereby further reduce the rateof advance to that appropriate for a heavier cut ting feed. This slowadvance of the tools continues until each is arrested by contact of-itsassociated stop 82 against the cooperating screw 78. Thereafter the slowad- Vance of the cross-head 47 continues until .stroke as hereinabovedescribe the pin-7O leaves the face 69. of cam block 66and shifts intocontact with face 63 of portion 62, whereupon .the pump reverses and thecross-heau begins 'a ra id return As the cross-head reverses .its motionthe several 7 feed pistons 25, 26, 27 and 28 are simultane ouslyactuated and begin a'rapid return movement withdrawing the several toolsfrom the pin-70' wit the face 64 of about the time the pin reac work.This movement of the tools continues until the s eed is reduced bycontact ofthe lportion 62, and

es the. straight portion of portion 62 the several stops 82 engage thescrews 79 and the several'feed pistons and'tools come to rest..Thereafter the cross-head 47 continues its return move.-

ment, but at a gradually reduced rate until Y .the pin is returned toneutral osition by the action of face 64 and the crosso r if-5 a It willbe noted that the ciit becomes considerably heavier as the was, near theend of their forward feeding stroke,engage their respective crankpins,and in order to avoid ead comes an excessive peak load on the machinefrom this cause, provision is'preferably made by 1 which the severaltools may be advanced into contact with their respective crank pinssuccessively rather than simultanenously. This is accomplished by soadjustinfg the several screws 79 as to stop the several eed cylindersand tools at diflerent points in their return strokes. For example,asindicated in Figure 5, the feed piston 25 has been permitted to.returna greater distance than the feed pis ton 26, by reason of avariation the settin of t eir respective stop screws 79, and tool 34(connected with p1ston,26) is correspondingly advanced with respecttotool 33 (connected with piston 25). Both tools 33 and 34 move forwardlysimultaneously and at the same rate during the next advance stroke ofthe cross-head 47, with the result that tool 34, in advance of tool 33,actually engages its crank pin and completesthe cut thereon pin.

Provision is also preferably made for concentrating the entire force ofthe power source upon any oneof the several tools to thereby renderavailable a pulling force of sufficient magnitude to extract a tool fromthe work in the event of a jam. To this end pro-, vislon is made forrendering any of the several high pressure relief valves 108 ineffectiveand for adjusting and retaining any of the check. valves 114 in openposition. In this instance a valve in the form of a stem 118, is

screwed into the rail 84 beneath each relief valve 108, and is providedwith a tapered end 119 adapted to enter and close 120 of the reliefvalve, to thereby render the same ineffective; and a stem 121 isscrewedbefore tool 33 reaches its crank the inlet port impellercylinders, are opened by adjustment i v of their respective stems 121 inthe manner just described so these three leads are all open to the lowpressure passage 112. With the valves thus adjusted the cross-head 47-is made to executea return stroke, and since the three impeller pistons44, 45, and '46 offer no appreciable resistance to this movement of thecross-head practically the entire force of the motor cylinder 59 isconcentrated upon the impeller through the lead 42to cylinder 21 at highpressure. Since the relief valve 108 connected with this lead has beenrenderedineffective,

thepressure therein is limited only by the force transmitted fromthemotor cylinder through piston 43; isordinarily sufficient'to extract theto i Various changes may-i be made inithe empiston 43, to thereby forceliquid bodiment of the invention hereinabove specifically describedwithout departingfrom or sacrificing the invention as defined in the appended claims. 1 .Iclaim:-'. I v 1. In a multiple hydraulic drive systemthe combination of a pl rality of liquid impelling means, means foraneously driv ng the same at regulated rates, a (plurality of sepaliquidimp ously rec procating the same at regulated rates, a plurality ofseparate hydraulically actuated reciprocating means, separate hydraulicconnectionsbetween said plurality of impelling means and said pluralityof actuated means through which said actuated means are individuallyreciprocated at regulated rates, and hydraulic compensating meansautomatically'operable to maintain a definite operating phase relationbetween said and an adfusta plurality of actuated means.

3. In a multiple hydraulic drive system the combination of a pluralityof impeller cylin-. ders and coacting pistons, means for effectingrelative reciprocation between said pistons and cylinders simultaneouslyand at regulated rates, a second pluralit of cylinders and coactingpistons, indivi ual hydraulic connections between said first and secondnamed cylinders, respectively, for efi'ectin relative reciprocationbetween said secon plurality of cylinders and coacting pistons atregulated rates, and hydraulic compensating means automaticall operableto maintain a definite operating p ase relation between said secondpluralityof cylinders and mad:- ing pistons.

4.. In a mi lgifple hydraulic drive system the combination a pluralityof reciprocating liquid im elling means, means for simultaneouslyreciprocating the same, a plurality of separate hydraulically actuatedreciprocating means, se arate hydraulic connections between saiplurality of impelling means and said plurality of actuated means,respectively, through which the latter are individually reciprocated,and means for arresting the motion of said actuated means prior to thecompletion of each stroke ofsaid connected'impelling means,respectively. 7

v 5. In a multi le hydraulic drive system the combination 0? a pluralityof liqmd impelling means, means for simultaneously driving the same,'aplurality of separate hydraulically actuated means, separate hy-rdraulic connections through which each of saidlast named means isindividually driven. by one of said plurality of impelling means,

le stop for limiting the extentfof movement of each of said actuated 9means.

v 6. In a multiple hydraulic drive system the combination of a pluralityof liquid lmpelling means, means for simultaneousl driving the same,means for controlling the extent of movement of said impelling meanscollectively, a plurality of hydraulically actuated means each driven byone of said pluralit of.

1m lling means, and means for control in the extent of movement of saidplurality o actuated means individually.

7.- In a multiple hydraulic drive system the combination of a pluralityof liquid 1m(pelling means, means for simultaneously riving the'same, aplurality of hydraulically actuated means, separate hydraulicconnections through which said' last named means are individually drivenby said plurality of impelling means, respectively, means for revers;ing the direction of motion of said impelling means to thereby reversethe motion of said actuated means, and adjustable stops for limiting theextent of movement of said actuated means" in both directions of motion.

v 8. In a multiple-hydraulic drive system the combination of a pluralityof li uid impelling means, means for simultaneous y driving the same atregulated rates, means for regulating the rate and extent of movement ofsaid impelling means, a plurality of hydraulically actuated means eachdriven by one of said plurality of impelling means at ratescorresponding to the rate of movement of said impelling means, andadjustable stops for individually limiting the extent of movement ofsaid actuated means.

'9. In a multiple hydraulic drive system the combination of a pluralityof li uid impelling means, means for simultaneous y driving the same atregulated rates, means for automatically regulating the rate of movementof said impelling means, and a plurality of hydrauli- I callyactuatedmeans each driven by one of sai plurality of impelling'means at ratescorresponding to the rate of motion of said impelling means. 7 3

10. In a multiple hydraulic drive system the combination of a luralityof liquid impelling means, means or driving the same at regulated rates,means responsive to the movement of said driving means for automaticallyvarying the rate of movement of said impelling means, and a plurality ofhydraulically actuatedmeans each driven by one of said plurality ofimpelling means at 7 rates corresponding to the rate of movement of saidimpelling'means. 4

11. In a multiple h draulic drivesystem the combination of a pluralit ofliquid impelling means hydraulic. rivin m'eans therefor inclu 'ng avariable disp acement pump, means for varying pump dis lacement to varythe rate of movemento? said im lling means, and a plurality ofhydraulidy actuated means each drivenby one of sai plurality ofimpellingmeans at rates corresponding to th'e'rate of movement of saidimpelling means.

7 12. In a multiple ,hydraulic system thecombination of a plurality ofliquid impelling means, hydraulic drivin means therefor including avariable disp acemen't' pump, means responsive to the action of saiddriving means for regulating dump displacement, a plurality ofhydraulically actuated means each driven by one of said impelling means,and means for individually controlling the extent of movement of saidplura'hty of actuated means.

13. In a multiple hydraulic system the, combination of a, lurality ofliquid impellin means, hy raulic drivin means there or including avariable disp acement pump, means for regulating pump displacement toregulate the rate of movement of said impelling means, a plurality ofhydraulicall actuated means each individually driven by one of saidimpelling means, and means for controlling the extent of movement ofeach of said actuated'means'.

14. In a multiple hydraulic system the combination of a plurality ofliquid impelling means, hydraulic driving means there'- for including avariable displacement pump, a pluralit of hydraulically actuated means,an individual hydraulic connection between each of said impelling meansand one of said actuated means through which the latter are driven,positive stops for arresting the movement of said .actuated means, andliquid escape means within said connections permitting continued actionof said impelling means after said actuated means have stopped.

15. In a multiple hydraulic system the combination of a plurality ofliquid impelling means, means for driving the same in either direction,a plurality of hydraulically actuated means, a. separate, reversibleflow hydraulic'ci rcuit between each of said impelling means and one ofsaid actuated means through which the latter are driven, means includinga check valve associated with one side of each of said circuits forsupplying liquid under low pressure thereto, means including a checkvalve associated with the other side of,each of said'circuits forpermitting the -escape of liquid therefrom, and means for maintainingsaid last namedcheck valves closed during operation of said actu- 17; Ina hydraulic drive the combination sages therein, a pintle of a liquidimpeller, hydraulically actuated means, and a flexible llquid conductingconnection between said impeller and means throughwhich thelatterisdriven, said connection comprising a pair of links each having apair of separate liquid conducting pasforming a pivotal connectionbetween said links and having a pair of separate passages therein, sideports in said pintle each communicating with one of said pintle passagesand with one of said passages in one of said links, and additional sideports in said pintle each communicating with one of said pintle passagesand with one of said passages in the other of said links.

18. In a machine tool or the like the combination of a rotary workholder, a tool support operating to cause the tool to follow the workduring rotation of said holder, and a hydraulically actuated feedmechanism for the tool for advancing the tool into the work duringmovement of said holder and support.

19. In a machine tool or the like the combination of a rotary workholder, a plurality of separate tool supports operable to cause thesupported tools to follow different portions of the work during rotationof said holder, and hydraulically actuated feed mechanisms forsimultaneously advancing the tools into the work during movement of saidholder and work supports.

20. In a machine tool or the like the combination of a rotary workholder, a pluralityof separate tool supports operable to cause itssupported tools to; follow difierent parts of the work duringrotation ofsaid holder,

a hydraulically actuated feedmechanism for each tooli movable with itssupport, and means including a variable delivery pump for efiectingthesimultaneous operation of said feed mechanisms at predetermined rates.

21. In a machine tool or the like the combination of a plurality ofseparate feed mechanisms, hydraulically actuated means for drivingeach'feed mechanism, a variable displacement pump, and a hydraulic powertransmission system between said pump and means for efiecting thesimultaneous operation of said feed mechanisms at rates corresponding topump displacement.

22. In a multiple hydraulic drive the comf bination of a plurality ofseparate hydraulically actuated means, a variable displace-' ment "pump,and a hydraulicpower transmission system between said pump and means foreffecting the simultaneous operation of said means at ratescorresponding to pump displacement. v

23. In a multiple hydraulic drive the combination of a plurality ofseparate hydraulically actuated means, "a variable displacement pump, ahydraulic power transmission s stem between said pump and means forsimultaneously driving said separate means at rates corresponding topump displacement,

operatively related to .all of the pumps to operate the same, and meanscommon element.

25. In a machine tool, a series of tool holders and means for feedingthe same, comprising a series of operating members, a series ofcylinders, and pistons in the cylinders coupled to drive the saidoperating members, a series of pump elements arranged to supply fluid tothe series of cylinders so as to move 1 the pistons therein, a commonelement coupled mechanically to all of the pumps to o eratethe same, andmeans for driving e common element. a

26. In a machine tool, a series of tool holders and means for feedingthe same, comprisfor driving the ing a series of operating members, aseries of cylinders having pistons therein, said pistons 8Q beingcoupled to the operatlngmembers, a sec ond series of cylinders havingpistons therein, a common operating member for said last named pistons,and connectionsfrom the cylinders of the second series to the cylindersof the first series so arranged that a fluid set, in motion by thepistons of the second series enters the cylinders of the first seriesand op= crates the same.

27. In a machine tool, a series of tool holding a series ofoperatingmembers, a series of cylinders, and pistons in the cylinders co u-' pledto drive the said operating members, a series of pump elements arrangedto supply fluid to the series of cylinders so as to move the pistonstherein, a common element coupled mechanically to all of the pumps, tooperate the same, and means for driving the common element,. said meanscomprislng'a cylinder and a piston therein connected to the commonelement, and means for supplying fluid under pressure to operate thepiston last named. w i 28. In a machine tool, a series of tool hold inga series of operating members, a series of c linders, and pistons in thecylinders coupled to drive the said operating members, a series of pumpelements arranged to supply fluid to the series of cylinders so as tomove the pistons therein, a common element coupled mechanically toall ofthe pumps to operatethe same, and means for driving thecommon element,said means comprising a i cylinder and a piston therein connected to ersand means for feeding the same, comprisers and means for feeding thesame, comprisfluid at varylng opfluid to the series of cylinders so asto move the pistons therein, a common element coupled mechanically toall of the pumps to operate the same, and means for driving the socommon element, said means comprisin a cylinder and a piston thereinconnecte to the common element, and means for supplying fluid underressure to operate the piston last named, sai means being of a type todeliver a constant flow of fluid at varying opposing pressures, saidtool holders, operating members, cylinders and pistons being arranged asa series of tool operating systems said systems as 'a whole movablymounte with relation to said pumps, and flexible conduits connecting thepumps to said cylinders.

30. In a machine tool, a series of tool holders and means for feedingthe same, comprising a series of operating members, a series of 3cylinders, and pistons in the cylinders coupled to drive the saidoperating members, a series of pump elements arranged to supply fluid tothe series of cylinders so as to move the pistons therein, a commonelement coupled mechanically to all of the pumps to operate the same,and means for driving the common element, a control means for the saidmachine tool, and connections from said common member to operate saidcontrol means automatically. 31. In a machine tool, a series of toolholders and means for feeding the same, comprising a series ofoperatinmembers, a series 1 of cylinders, and pistons 1n the cylinders coupledto drive the said operating members, a series of pum elements arrangedto supply fluid tothe series of cylinders so as to move the pistonstherein, a common element operatively related toall of the pumps tooperate the same, and means for driving the common element,. each ofsaid tool holders having positive stops. 32. In a-machine tool, a seriesof tool holders and means for feeding the same, compris-- ing a seriesofoperating members, a series of c linders, and pistons in the cylinderscouple to drive the said operating members, a.

series of pump elements arranged to supply 4 fluid to the series ofcylinders so as to move .125

the pistons therein, a common element coupled mechanically to all of thepumps to operate the same, and means for driving the common element, acontrol means for the said machine tool, and connections from saidcommon member to operate said control means. automatically, each of saidtool holders having positive stops.

33. An hydraulically operated system for the operation of a series ofworking members of a machine tool comprising a source of hydraulicpressure of a type to deliver a constant flow of liquid at varyingpressures, a master cylinder to which liquid is delivered from saidsource, and a series of separate hydraulic power delivery systems, onefor each working member, each of said separate systems deriving itsenergy from said master cylinder. 34. An hydraulically operated systemfor the operation of a series of working members of a. machine toolcomprising a source of hydraulic pressure of a type to deliver a constant flow of liquid at varying pressures, a master cylinder to whichliquid is delivered from said source, and a series of separate hydraulicpower delivery systems, one for each working member, each of saidseparate systems deriving its energy from said master :5 cylinder, saidpower delivery systems each,

comprising a hydraulic cylinder and piston for each working member andmovable therewith, and flexible conduit means whereby hydraulic pressureis delivered to each of said cylinders.

In' 'tness whereof, I hereunto subscribe my name this 11th da ofFebruary, 1928. J OHN P. FERRIS.

